xref: /netbsd-src/sys/dev/vme/si.c (revision 3b01aba77a7a698587faaae455bbfe740923c1f5)
1 /*	$NetBSD: si.c,v 1.3 2001/04/25 17:53:43 bouyer Exp $	*/
2 
3 /*-
4  * Copyright (c) 1996,2000 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Adam Glass, David Jones, Gordon W. Ross, Jason R. Thorpe and
9  * Paul Kranenburg.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *        This product includes software developed by the NetBSD
22  *        Foundation, Inc. and its contributors.
23  * 4. Neither the name of The NetBSD Foundation nor the names of its
24  *    contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37  * POSSIBILITY OF SUCH DAMAGE.
38  */
39 
40 /*
41  * This file contains VME bus-dependent of the `si' SCSI adapter.
42  * This hardware is frequently found on Sun 3 and Sun 4 machines.
43  *
44  * The SCSI machinery on this adapter is implemented by an NCR5380,
45  * which is taken care of by the chipset driver in /sys/dev/ic/ncr5380sbc.c
46  *
47  * The logic has a bit to enable or disable the DMA engine,
48  * but that bit also gates the interrupt line from the NCR5380!
49  * Therefore, in order to get any interrupt from the 5380, (i.e.
50  * for reselect) one must clear the DMA engine transfer count and
51  * then enable DMA.  This has the further complication that you
52  * CAN NOT touch the NCR5380 while the DMA enable bit is set, so
53  * we have to turn DMA back off before we even look at the 5380.
54  *
55  * What wonderfully whacky hardware this is!
56  *
57  */
58 
59 /*
60  * This driver originated as an MD implementation for the sun3 and sun4
61  * ports. The notes pertaining to that history are included below.
62  *
63  * David Jones wrote the initial version of this module for NetBSD/sun3,
64  * which included support for the VME adapter only. (no reselection).
65  *
66  * Gordon Ross added support for the Sun 3 OBIO adapter, and re-worked
67  * both the VME and OBIO code to support disconnect/reselect.
68  * (Required figuring out the hardware "features" noted above.)
69  *
70  * The autoconfiguration boilerplate came from Adam Glass.
71  *
72  * Jason R. Thorpe ported the autoconfiguration and VME portions to
73  * NetBSD/sparc, and added initial support for the 4/100 "SCSI Weird",
74  * a wacky OBIO variant of the VME SCSI-3.  Many thanks to Chuck Cranor
75  * for lots of helpful tips and suggestions.  Thanks also to Paul Kranenburg
76  * and Chris Torek for bits of insight needed along the way.  Thanks to
77  * David Gilbert and Andrew Gillham who risked filesystem life-and-limb
78  * for the sake of testing.  Andrew Gillham helped work out the bugs
79  * the 4/100 DMA code.
80  */
81 
82 #include "opt_ddb.h"
83 
84 #include <sys/types.h>
85 #include <sys/param.h>
86 #include <sys/systm.h>
87 #include <sys/kernel.h>
88 #include <sys/malloc.h>
89 #include <sys/errno.h>
90 #include <sys/device.h>
91 #include <sys/buf.h>
92 
93 #include <machine/bus.h>
94 #include <machine/intr.h>
95 
96 #include <dev/vme/vmereg.h>
97 #include <dev/vme/vmevar.h>
98 
99 #include <dev/scsipi/scsi_all.h>
100 #include <dev/scsipi/scsipi_all.h>
101 #include <dev/scsipi/scsipi_debug.h>
102 #include <dev/scsipi/scsiconf.h>
103 
104 #ifndef DDB
105 #define	Debugger()
106 #endif
107 
108 #ifndef DEBUG
109 #define DEBUG XXX
110 #endif
111 
112 #include <dev/ic/ncr5380reg.h>
113 #include <dev/ic/ncr5380var.h>
114 
115 #include <dev/vme/sireg.h>
116 
117 /*
118  * Transfers smaller than this are done using PIO
119  * (on assumption they're not worth DMA overhead)
120  */
121 #define	MIN_DMA_LEN 128
122 
123 #ifdef	DEBUG
124 int si_debug = 0;
125 #endif
126 
127 /*
128  * This structure is used to keep track of mapped DMA requests.
129  */
130 struct si_dma_handle {
131 	int 		dh_flags;
132 #define	SIDH_BUSY	0x01		/* This DH is in use */
133 #define	SIDH_OUT	0x02		/* DMA does data out (write) */
134 	int 		dh_maplen;	/* Original data length */
135 	bus_dmamap_t	dh_dmamap;
136 #define dh_dvma	dh_dmamap->dm_segs[0].ds_addr /* VA of buffer in DVMA space */
137 };
138 
139 /*
140  * The first structure member has to be the ncr5380_softc
141  * so we can just cast to go back and fourth between them.
142  */
143 struct si_softc {
144 	struct ncr5380_softc	ncr_sc;
145 	bus_space_tag_t		sc_bustag;	/* bus tags */
146 	bus_dma_tag_t		sc_dmatag;
147 	vme_chipset_tag_t	sc_vctag;
148 
149 	int		sc_adapter_iv_am; /* int. vec + address modifier */
150 	struct si_dma_handle *sc_dma;
151 	int		sc_xlen;	/* length of current DMA segment. */
152 	int		sc_options;	/* options for this instance. */
153 };
154 
155 /*
156  * Options.  By default, DMA is enabled and DMA completion interrupts
157  * and reselect are disabled.  You may enable additional features
158  * the `flags' directive in your kernel's configuration file.
159  *
160  * Alternatively, you can patch your kernel with DDB or some other
161  * mechanism.  The sc_options member of the softc is OR'd with
162  * the value in si_options.
163  *
164  * Note, there's a separate sw_options to make life easier.
165  */
166 #define	SI_ENABLE_DMA	0x01	/* Use DMA (maybe polled) */
167 #define	SI_DMA_INTR	0x02	/* DMA completion interrupts */
168 #define	SI_DO_RESELECT	0x04	/* Allow disconnect/reselect */
169 #define	SI_OPTIONS_MASK	(SI_ENABLE_DMA|SI_DMA_INTR|SI_DO_RESELECT)
170 #define SI_OPTIONS_BITS	"\10\3RESELECT\2DMA_INTR\1DMA"
171 int si_options = SI_ENABLE_DMA|SI_DMA_INTR|SI_DO_RESELECT;
172 
173 static int	si_match __P((struct device *, struct cfdata *, void *));
174 static void	si_attach __P((struct device *, struct device *, void *));
175 static int	si_intr __P((void *));
176 static void	si_reset_adapter __P((struct ncr5380_softc *));
177 
178 void	si_dma_alloc __P((struct ncr5380_softc *));
179 void	si_dma_free __P((struct ncr5380_softc *));
180 void	si_dma_poll __P((struct ncr5380_softc *));
181 
182 void	si_dma_setup __P((struct ncr5380_softc *));
183 void	si_dma_start __P((struct ncr5380_softc *));
184 void	si_dma_eop __P((struct ncr5380_softc *));
185 void	si_dma_stop __P((struct ncr5380_softc *));
186 
187 void	si_intr_on  __P((struct ncr5380_softc *));
188 void	si_intr_off __P((struct ncr5380_softc *));
189 
190 /*
191  * Shorthand bus space access
192  * XXX - must look into endian issues here.
193  */
194 #define SIREG_READ(sc, index) \
195 	bus_space_read_2((sc)->sc_regt, (sc)->sc_regh, index)
196 #define SIREG_WRITE(sc, index, v) \
197 	bus_space_write_2((sc)->sc_regt, (sc)->sc_regh, index, v)
198 
199 
200 /* Auto-configuration glue. */
201 struct cfattach si_ca = {
202 	sizeof(struct si_softc), si_match, si_attach
203 };
204 
205 static int
206 si_match(parent, cf, aux)
207 	struct device	*parent;
208 	struct cfdata *cf;
209 	void *aux;
210 {
211 	struct vme_attach_args	*va = aux;
212 	vme_chipset_tag_t	ct = va->va_vct;
213         vme_am_t		mod;
214         vme_addr_t		vme_addr;
215 
216 	/* Make sure there is something there... */
217 	mod = VME_AM_A24 | VME_AM_MBO | VME_AM_SUPER | VME_AM_DATA;
218 	vme_addr = va->r[0].offset;
219 
220 	if (vme_probe(ct, vme_addr, 1, mod, VME_D8, NULL, 0) != 0)
221 		return (0);
222 
223 	/*
224 	 * If this is a VME SCSI board, we have to determine whether
225 	 * it is an "sc" (Sun2) or "si" (Sun3) SCSI board.  This can
226 	 * be determined using the fact that the "sc" board occupies
227 	 * 4K bytes in VME space but the "si" board occupies 2K bytes.
228 	 */
229 	return (vme_probe(ct, vme_addr + 0x801, 1, mod, VME_D8, NULL, 0) != 0);
230 }
231 
232 static void
233 si_attach(parent, self, aux)
234 	struct device	*parent, *self;
235 	void		*aux;
236 {
237 	struct si_softc		*sc = (struct si_softc *) self;
238 	struct ncr5380_softc *ncr_sc = &sc->ncr_sc;
239 	struct vme_attach_args	*va = aux;
240 	vme_chipset_tag_t	ct = va->va_vct;
241 	bus_space_tag_t		bt;
242 	bus_space_handle_t	bh;
243 	vme_mapresc_t resc;
244 	vme_intr_handle_t	ih;
245 	vme_am_t		mod;
246 	char bits[64];
247 	int i;
248 
249 	sc->sc_dmatag = va->va_bdt;
250 	sc->sc_vctag = ct;
251 
252 	mod = VME_AM_A24 | VME_AM_MBO | VME_AM_SUPER | VME_AM_DATA;
253 
254 	if (vme_space_map(ct, va->r[0].offset, SIREG_BANK_SZ,
255 			  mod, VME_D8, 0, &bt, &bh, &resc) != 0)
256 		panic("%s: vme_space_map", ncr_sc->sc_dev.dv_xname);
257 
258 	ncr_sc->sc_regt = bt;
259 	ncr_sc->sc_regh = bh;
260 
261 	sc->sc_options = si_options;
262 
263 	ncr_sc->sc_dma_setup = si_dma_setup;
264 	ncr_sc->sc_dma_start = si_dma_start;
265 	ncr_sc->sc_dma_eop   = si_dma_stop;
266 	ncr_sc->sc_dma_stop  = si_dma_stop;
267 
268 	vme_intr_map(ct, va->ilevel, va->ivector, &ih);
269 	vme_intr_establish(ct, ih, IPL_BIO, si_intr, sc);
270 
271 	printf("\n");
272 
273 	sc->sc_adapter_iv_am = (mod << 8) | (va->ivector & 0xFF);
274 
275 	/*
276 	 * Pull in the options flags.  Allow the user to completely
277 	 * override the default values.
278 	 */
279 	if ((ncr_sc->sc_dev.dv_cfdata->cf_flags & SI_OPTIONS_MASK) != 0)
280 		sc->sc_options =
281 		    (ncr_sc->sc_dev.dv_cfdata->cf_flags & SI_OPTIONS_MASK);
282 
283 	/*
284 	 * Initialize fields used by the MI code
285 	 */
286 
287 	/* NCR5380 register bank offsets */
288 	ncr_sc->sci_r0 = 0;
289 	ncr_sc->sci_r1 = 1;
290 	ncr_sc->sci_r2 = 2;
291 	ncr_sc->sci_r3 = 3;
292 	ncr_sc->sci_r4 = 4;
293 	ncr_sc->sci_r5 = 5;
294 	ncr_sc->sci_r6 = 6;
295 	ncr_sc->sci_r7 = 7;
296 
297 	ncr_sc->sc_rev = NCR_VARIANT_NCR5380;
298 
299 	/*
300 	 * MD function pointers used by the MI code.
301 	 */
302 	ncr_sc->sc_pio_out = ncr5380_pio_out;
303 	ncr_sc->sc_pio_in =  ncr5380_pio_in;
304 	ncr_sc->sc_dma_alloc = si_dma_alloc;
305 	ncr_sc->sc_dma_free  = si_dma_free;
306 	ncr_sc->sc_dma_poll  = si_dma_poll;
307 
308 	ncr_sc->sc_flags = 0;
309 	if ((sc->sc_options & SI_DO_RESELECT) == 0)
310 		ncr_sc->sc_no_disconnect = 0xFF;
311 	if ((sc->sc_options & SI_DMA_INTR) == 0)
312 		ncr_sc->sc_flags |= NCR5380_FORCE_POLLING;
313 	ncr_sc->sc_min_dma_len = MIN_DMA_LEN;
314 
315 	/*
316 	 * Allocate DMA handles.
317 	 */
318 	i = SCI_OPENINGS * sizeof(struct si_dma_handle);
319 	sc->sc_dma = (struct si_dma_handle *)malloc(i, M_DEVBUF, M_NOWAIT);
320 	if (sc->sc_dma == NULL)
321 		panic("si: dma handle malloc failed\n");
322 
323 	for (i = 0; i < SCI_OPENINGS; i++) {
324 		sc->sc_dma[i].dh_flags = 0;
325 
326 		/* Allocate a DMA handle */
327 		if (vme_dmamap_create(
328 				sc->sc_vctag,	/* VME chip tag */
329 				MAXPHYS,	/* size */
330 				VME_AM_A24,	/* address modifier */
331 				VME_D16,	/* data size */
332 				0,		/* swap */
333 				1,		/* nsegments */
334 				MAXPHYS,	/* maxsegsz */
335 				0,		/* boundary */
336 				BUS_DMA_NOWAIT,
337 				&sc->sc_dma[i].dh_dmamap) != 0) {
338 
339 			printf("%s: DMA buffer map create error\n",
340 				ncr_sc->sc_dev.dv_xname);
341 			return;
342 		}
343 	}
344 
345 	if (sc->sc_options) {
346 		printf("%s: options=%s\n", ncr_sc->sc_dev.dv_xname,
347 			bitmask_snprintf(sc->sc_options, SI_OPTIONS_BITS,
348 			    bits, sizeof(bits)));
349 	}
350 
351 	ncr_sc->sc_channel.chan_id = 7;
352 	ncr_sc->sc_adapter.adapt_minphys = minphys;
353 
354 	/*
355 	 *  Initialize si board itself.
356 	 */
357 	si_reset_adapter(ncr_sc);
358 	ncr5380_attach(ncr_sc);
359 
360 	if (sc->sc_options & SI_DO_RESELECT) {
361 		/*
362 		 * Need to enable interrupts (and DMA!)
363 		 * on this H/W for reselect to work.
364 		 */
365 		ncr_sc->sc_intr_on   = si_intr_on;
366 		ncr_sc->sc_intr_off  = si_intr_off;
367 	}
368 }
369 
370 #define CSR_WANT (SI_CSR_SBC_IP | SI_CSR_DMA_IP | \
371 	SI_CSR_DMA_CONFLICT | SI_CSR_DMA_BUS_ERR )
372 
373 static int
374 si_intr(void *arg)
375 {
376 	struct si_softc *sc = arg;
377 	struct ncr5380_softc *ncr_sc = (struct ncr5380_softc *)arg;
378 	int dma_error, claimed;
379 	u_short csr;
380 
381 	claimed = 0;
382 	dma_error = 0;
383 
384 	/* SBC interrupt? DMA interrupt? */
385 	csr = SIREG_READ(ncr_sc, SIREG_CSR);
386 
387 	NCR_TRACE("si_intr: csr=0x%x\n", csr);
388 
389 	if (csr & SI_CSR_DMA_CONFLICT) {
390 		dma_error |= SI_CSR_DMA_CONFLICT;
391 		printf("si_intr: DMA conflict\n");
392 	}
393 	if (csr & SI_CSR_DMA_BUS_ERR) {
394 		dma_error |= SI_CSR_DMA_BUS_ERR;
395 		printf("si_intr: DMA bus error\n");
396 	}
397 	if (dma_error) {
398 		if (sc->ncr_sc.sc_state & NCR_DOINGDMA)
399 			sc->ncr_sc.sc_state |= NCR_ABORTING;
400 		/* Make sure we will call the main isr. */
401 		csr |= SI_CSR_DMA_IP;
402 	}
403 
404 	if (csr & (SI_CSR_SBC_IP | SI_CSR_DMA_IP)) {
405 		claimed = ncr5380_intr(&sc->ncr_sc);
406 #ifdef DEBUG
407 		if (!claimed) {
408 			printf("si_intr: spurious from SBC\n");
409 			if (si_debug & 4) {
410 				Debugger();	/* XXX */
411 			}
412 		}
413 #endif
414 	}
415 
416 	return (claimed);
417 }
418 
419 
420 static void
421 si_reset_adapter(struct ncr5380_softc *ncr_sc)
422 {
423 	struct si_softc *sc = (struct si_softc *)ncr_sc;
424 
425 #ifdef	DEBUG
426 	if (si_debug) {
427 		printf("si_reset_adapter\n");
428 	}
429 #endif
430 
431 	/*
432 	 * The SCSI3 controller has an 8K FIFO to buffer data between the
433 	 * 5380 and the DMA.  Make sure it starts out empty.
434 	 *
435 	 * The reset bits in the CSR are active low.
436 	 */
437 	SIREG_WRITE(ncr_sc, SIREG_CSR, 0);
438 	delay(10);
439 	SIREG_WRITE(ncr_sc, SIREG_CSR,
440 			SI_CSR_FIFO_RES | SI_CSR_SCSI_RES | SI_CSR_INTR_EN);
441 	delay(10);
442 
443 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNT, 0);
444 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRH, 0);
445 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRL, 0);
446 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTH, 0);
447 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTL, 0);
448 	SIREG_WRITE(ncr_sc, SIREG_IV_AM, sc->sc_adapter_iv_am);
449 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNTH, 0);
450 
451 	SCI_CLR_INTR(ncr_sc);
452 }
453 
454 /*****************************************************************
455  * Common functions for DMA
456  ****************************************************************/
457 
458 /*
459  * Allocate a DMA handle and put it in sc->sc_dma.  Prepare
460  * for DMA transfer.
461  */
462 void
463 si_dma_alloc(ncr_sc)
464 	struct ncr5380_softc *ncr_sc;
465 {
466 	struct si_softc *sc = (struct si_softc *)ncr_sc;
467 	struct sci_req *sr = ncr_sc->sc_current;
468 	struct scsipi_xfer *xs = sr->sr_xs;
469 	struct si_dma_handle *dh;
470 	int i, xlen;
471 	u_long addr;
472 
473 #ifdef DIAGNOSTIC
474 	if (sr->sr_dma_hand != NULL)
475 		panic("si_dma_alloc: already have DMA handle");
476 #endif
477 
478 #if 1	/* XXX - Temporary */
479 	/* XXX - In case we think DMA is completely broken... */
480 	if ((sc->sc_options & SI_ENABLE_DMA) == 0)
481 		return;
482 #endif
483 
484 	addr = (u_long) ncr_sc->sc_dataptr;
485 	xlen = ncr_sc->sc_datalen;
486 
487 	/* If the DMA start addr is misaligned then do PIO */
488 	if ((addr & 1) || (xlen & 1)) {
489 		printf("si_dma_alloc: misaligned.\n");
490 		return;
491 	}
492 
493 	/* Make sure our caller checked sc_min_dma_len. */
494 	if (xlen < MIN_DMA_LEN)
495 		panic("si_dma_alloc: xlen=0x%x\n", xlen);
496 
497 	/* Find free DMA handle.  Guaranteed to find one since we have
498 	   as many DMA handles as the driver has processes. */
499 	for (i = 0; i < SCI_OPENINGS; i++) {
500 		if ((sc->sc_dma[i].dh_flags & SIDH_BUSY) == 0)
501 			goto found;
502 	}
503 	panic("si: no free DMA handles.");
504 
505 found:
506 	dh = &sc->sc_dma[i];
507 	dh->dh_flags = SIDH_BUSY;
508 	dh->dh_maplen  = xlen;
509 
510 	/* Copy the "write" flag for convenience. */
511 	if ((xs->xs_control & XS_CTL_DATA_OUT) != 0)
512 		dh->dh_flags |= SIDH_OUT;
513 
514 	/*
515 	 * Double-map the buffer into DVMA space.  If we can't re-map
516 	 * the buffer, we print a warning and fall back to PIO mode.
517 	 *
518 	 * NOTE: it is not safe to sleep here!
519 	 */
520 	if (bus_dmamap_load(sc->sc_dmatag, dh->dh_dmamap,
521 			    (caddr_t)addr, xlen, NULL, BUS_DMA_NOWAIT) != 0) {
522 		/* Can't remap segment */
523 		printf("si_dma_alloc: can't remap 0x%lx/0x%x, doing PIO\n",
524 			addr, dh->dh_maplen);
525 		dh->dh_flags = 0;
526 		return;
527 	}
528 	bus_dmamap_sync(sc->sc_dmatag, dh->dh_dmamap, addr, xlen,
529 			(dh->dh_flags & SIDH_OUT)
530 				? BUS_DMASYNC_PREWRITE
531 				: BUS_DMASYNC_PREREAD);
532 
533 	/* success */
534 	sr->sr_dma_hand = dh;
535 
536 	return;
537 }
538 
539 
540 void
541 si_dma_free(ncr_sc)
542 	struct ncr5380_softc *ncr_sc;
543 {
544 	struct si_softc *sc = (struct si_softc *)ncr_sc;
545 	struct sci_req *sr = ncr_sc->sc_current;
546 	struct si_dma_handle *dh = sr->sr_dma_hand;
547 
548 #ifdef DIAGNOSTIC
549 	if (dh == NULL)
550 		panic("si_dma_free: no DMA handle");
551 #endif
552 
553 	if (ncr_sc->sc_state & NCR_DOINGDMA)
554 		panic("si_dma_free: free while in progress");
555 
556 	if (dh->dh_flags & SIDH_BUSY) {
557 		/* Give back the DVMA space. */
558 		bus_dmamap_sync(sc->sc_dmatag, dh->dh_dmamap,
559 				dh->dh_dvma, dh->dh_maplen,
560 				(dh->dh_flags & SIDH_OUT)
561 					? BUS_DMASYNC_POSTWRITE
562 					: BUS_DMASYNC_POSTREAD);
563 		bus_dmamap_unload(sc->sc_dmatag, dh->dh_dmamap);
564 		dh->dh_flags = 0;
565 	}
566 	sr->sr_dma_hand = NULL;
567 }
568 
569 
570 /*
571  * Poll (spin-wait) for DMA completion.
572  * Called right after xx_dma_start(), and
573  * xx_dma_stop() will be called next.
574  * Same for either VME or OBIO.
575  */
576 void
577 si_dma_poll(ncr_sc)
578 	struct ncr5380_softc *ncr_sc;
579 {
580 	struct sci_req *sr = ncr_sc->sc_current;
581 	int tmo, csr_mask, csr;
582 
583 	/* Make sure DMA started successfully. */
584 	if (ncr_sc->sc_state & NCR_ABORTING)
585 		return;
586 
587 	csr_mask = SI_CSR_SBC_IP | SI_CSR_DMA_IP |
588 		SI_CSR_DMA_CONFLICT | SI_CSR_DMA_BUS_ERR;
589 
590 	tmo = 50000;	/* X100 = 5 sec. */
591 	for (;;) {
592 		csr = SIREG_READ(ncr_sc, SIREG_CSR);
593 		if (csr & csr_mask)
594 			break;
595 		if (--tmo <= 0) {
596 			printf("%s: DMA timeout (while polling)\n",
597 			    ncr_sc->sc_dev.dv_xname);
598 			/* Indicate timeout as MI code would. */
599 			sr->sr_flags |= SR_OVERDUE;
600 			break;
601 		}
602 		delay(100);
603 	}
604 
605 #ifdef	DEBUG
606 	if (si_debug) {
607 		printf("si_dma_poll: done, csr=0x%x\n", csr);
608 	}
609 #endif
610 }
611 
612 
613 /*****************************************************************
614  * VME functions for DMA
615  ****************************************************************/
616 
617 
618 /*
619  * This is called when the bus is going idle,
620  * so we want to enable the SBC interrupts.
621  * That is controlled by the DMA enable!
622  * Who would have guessed!
623  * What a NASTY trick!
624  */
625 void
626 si_intr_on(ncr_sc)
627 	struct ncr5380_softc *ncr_sc;
628 {
629 	u_int16_t csr;
630 
631 	si_dma_setup(ncr_sc);
632 	csr = SIREG_READ(ncr_sc, SIREG_CSR);
633 	csr |= SI_CSR_DMA_EN;
634 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
635 }
636 
637 /*
638  * This is called when the bus is idle and we are
639  * about to start playing with the SBC chip.
640  */
641 void
642 si_intr_off(ncr_sc)
643 	struct ncr5380_softc *ncr_sc;
644 {
645 	u_int16_t csr;
646 
647 	csr = SIREG_READ(ncr_sc, SIREG_CSR);
648 	csr &= ~SI_CSR_DMA_EN;
649 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
650 }
651 
652 /*
653  * This function is called during the COMMAND or MSG_IN phase
654  * that preceeds a DATA_IN or DATA_OUT phase, in case we need
655  * to setup the DMA engine before the bus enters a DATA phase.
656  *
657  * XXX: The VME adapter appears to suppress SBC interrupts
658  * when the FIFO is not empty or the FIFO count is non-zero!
659  *
660  * On the VME version we just clear the DMA count and address
661  * here (to make sure it stays idle) and do the real setup
662  * later, in dma_start.
663  */
664 void
665 si_dma_setup(ncr_sc)
666 	struct ncr5380_softc *ncr_sc;
667 {
668 	u_int16_t csr;
669 
670 	csr = SIREG_READ(ncr_sc, SIREG_CSR);
671 
672 	/* Reset the FIFO */
673 	csr &= ~SI_CSR_FIFO_RES;		/* active low */
674 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
675 	csr |= SI_CSR_FIFO_RES;
676 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
677 
678 	/* Set direction (assume recv here) */
679 	csr &= ~SI_CSR_SEND;
680 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
681 	/* Assume worst alignment */
682 	csr |= SI_CSR_BPCON;
683 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
684 
685 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRH, 0);
686 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRL, 0);
687 
688 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTH, 0);
689 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTL, 0);
690 
691 	/* Clear FIFO counter. (also hits dma_count) */
692 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNTH, 0);
693 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNT, 0);
694 }
695 
696 
697 void
698 si_dma_start(ncr_sc)
699 	struct ncr5380_softc *ncr_sc;
700 {
701 	struct si_softc *sc = (struct si_softc *)ncr_sc;
702 	struct sci_req *sr = ncr_sc->sc_current;
703 	struct si_dma_handle *dh = sr->sr_dma_hand;
704 	u_long dva;
705 	int xlen;
706 	u_int mode;
707 	u_int16_t csr;
708 
709 	/*
710 	 * Get the DVMA mapping for this segment.
711 	 */
712 	dva = (u_long)(dh->dh_dvma);
713 	if (dva & 1)
714 		panic("si_dma_start: bad dmaaddr=0x%lx", dva);
715 	xlen = ncr_sc->sc_datalen;
716 	xlen &= ~1;
717 	sc->sc_xlen = xlen;	/* XXX: or less... */
718 
719 #ifdef	DEBUG
720 	if (si_debug & 2) {
721 		printf("si_dma_start: dh=%p, dmaaddr=0x%lx, xlen=%d\n",
722 			   dh, dva, xlen);
723 	}
724 #endif
725 
726 	/*
727 	 * Set up the DMA controller.
728 	 * Note that (dh->dh_len < sc_datalen)
729 	 */
730 
731 	csr = SIREG_READ(ncr_sc, SIREG_CSR);
732 
733 	/* Disable DMA while we're setting up the transfer */
734 	csr &= ~SI_CSR_DMA_EN;
735 
736 	/* Reset FIFO (again?) */
737 	csr &= ~SI_CSR_FIFO_RES;		/* active low */
738 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
739 	csr |= SI_CSR_FIFO_RES;
740 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
741 
742 	/* Set direction (send/recv) */
743 	if (dh->dh_flags & SIDH_OUT) {
744 		csr |= SI_CSR_SEND;
745 	} else {
746 		csr &= ~SI_CSR_SEND;
747 	}
748 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
749 
750 	if (dva & 2) {
751 		csr |= SI_CSR_BPCON;
752 	} else {
753 		csr &= ~SI_CSR_BPCON;
754 	}
755 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
756 
757 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRH, (u_int16_t)(dva >> 16));
758 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRL, (u_int16_t)(dva & 0xFFFF));
759 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTH, (u_int16_t)(xlen >> 16));
760 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTL, (u_int16_t)(xlen & 0xFFFF));
761 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNTH, (u_int16_t)(xlen >> 16));
762 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNT, (u_int16_t)(xlen & 0xFFFF));
763 
764 	/*
765 	 * Acknowledge the phase change.  (After DMA setup!)
766 	 * Put the SBIC into DMA mode, and start the transfer.
767 	 */
768 	if (dh->dh_flags & SIDH_OUT) {
769 		NCR5380_WRITE(ncr_sc, sci_tcmd, PHASE_DATA_OUT);
770 		SCI_CLR_INTR(ncr_sc);
771 		NCR5380_WRITE(ncr_sc, sci_icmd, SCI_ICMD_DATA);
772 
773 		mode = NCR5380_READ(ncr_sc, sci_mode);
774 		mode |= (SCI_MODE_DMA | SCI_MODE_DMA_IE);
775 		NCR5380_WRITE(ncr_sc, sci_mode, mode);
776 
777 		NCR5380_WRITE(ncr_sc, sci_dma_send, 0); /* start it */
778 	} else {
779 		NCR5380_WRITE(ncr_sc, sci_tcmd, PHASE_DATA_IN);
780 		SCI_CLR_INTR(ncr_sc);
781 		NCR5380_WRITE(ncr_sc, sci_icmd, 0);
782 
783 		mode = NCR5380_READ(ncr_sc, sci_mode);
784 		mode |= (SCI_MODE_DMA | SCI_MODE_DMA_IE);
785 		NCR5380_WRITE(ncr_sc, sci_mode, mode);
786 
787 		NCR5380_WRITE(ncr_sc, sci_irecv, 0); /* start it */
788 	}
789 
790 	/* Enable DMA engine */
791 	csr |= SI_CSR_DMA_EN;
792 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
793 
794 	ncr_sc->sc_state |= NCR_DOINGDMA;
795 
796 #ifdef	DEBUG
797 	if (si_debug & 2) {
798 		printf("si_dma_start: started, flags=0x%x\n",
799 			   ncr_sc->sc_state);
800 	}
801 #endif
802 }
803 
804 
805 void
806 si_dma_eop(ncr_sc)
807 	struct ncr5380_softc *ncr_sc;
808 {
809 
810 	/* Not needed - DMA was stopped prior to examining sci_csr */
811 }
812 
813 
814 void
815 si_dma_stop(ncr_sc)
816 	struct ncr5380_softc *ncr_sc;
817 {
818 	struct si_softc *sc = (struct si_softc *)ncr_sc;
819 	struct sci_req *sr = ncr_sc->sc_current;
820 	struct si_dma_handle *dh = sr->sr_dma_hand;
821 	int resid, ntrans;
822 	u_int16_t csr;
823 	u_int mode;
824 
825 	if ((ncr_sc->sc_state & NCR_DOINGDMA) == 0) {
826 #ifdef	DEBUG
827 		printf("si_dma_stop: dma not running\n");
828 #endif
829 		return;
830 	}
831 
832 	ncr_sc->sc_state &= ~NCR_DOINGDMA;
833 
834 	csr = SIREG_READ(ncr_sc, SIREG_CSR);
835 
836 	/* First, halt the DMA engine. */
837 	csr &= ~SI_CSR_DMA_EN;
838 	SIREG_WRITE(ncr_sc, SIREG_CSR, csr);
839 
840 	if (csr & (SI_CSR_DMA_CONFLICT | SI_CSR_DMA_BUS_ERR)) {
841 		printf("si: DMA error, csr=0x%x, reset\n", csr);
842 		sr->sr_xs->error = XS_DRIVER_STUFFUP;
843 		ncr_sc->sc_state |= NCR_ABORTING;
844 		si_reset_adapter(ncr_sc);
845 	}
846 
847 	/* Note that timeout may have set the error flag. */
848 	if (ncr_sc->sc_state & NCR_ABORTING)
849 		goto out;
850 
851 	/*
852 	 * Now try to figure out how much actually transferred
853 	 *
854 	 * The fifo_count does not reflect how many bytes were
855 	 * actually transferred for VME.
856 	 *
857 	 * SCSI-3 VME interface is a little funny on writes:
858 	 * if we have a disconnect, the dma has overshot by
859 	 * one byte and the resid needs to be incremented.
860 	 * Only happens for partial transfers.
861 	 * (Thanks to Matt Jacob)
862 	 */
863 
864 	resid = SIREG_READ(ncr_sc, SIREG_FIFO_CNTH) << 16;
865 	resid |= SIREG_READ(ncr_sc, SIREG_FIFO_CNT) & 0xFFFF;
866 	if (dh->dh_flags & SIDH_OUT)
867 		if ((resid > 0) && (resid < sc->sc_xlen))
868 			resid++;
869 	ntrans = sc->sc_xlen - resid;
870 
871 #ifdef	DEBUG
872 	if (si_debug & 2) {
873 		printf("si_dma_stop: resid=0x%x ntrans=0x%x\n",
874 		    resid, ntrans);
875 	}
876 #endif
877 
878 	if (ntrans > ncr_sc->sc_datalen)
879 		panic("si_dma_stop: excess transfer");
880 
881 	/* Adjust data pointer */
882 	ncr_sc->sc_dataptr += ntrans;
883 	ncr_sc->sc_datalen -= ntrans;
884 
885 #ifdef	DEBUG
886 	if (si_debug & 2) {
887 		printf("si_dma_stop: ntrans=0x%x\n", ntrans);
888 	}
889 #endif
890 
891 	/*
892 	 * After a read, we may need to clean-up
893 	 * "Left-over bytes" (yuck!)
894 	 */
895 	if (((dh->dh_flags & SIDH_OUT) == 0) &&
896 		((csr & SI_CSR_LOB) != 0))
897 	{
898 		char *cp = ncr_sc->sc_dataptr;
899 		u_int16_t bprh, bprl;
900 
901 		bprh = SIREG_READ(ncr_sc, SIREG_BPRH);
902 		bprl = SIREG_READ(ncr_sc, SIREG_BPRL);
903 
904 #ifdef DEBUG
905 		printf("si: got left-over bytes: bprh=%x, bprl=%x, csr=%x\n",
906 			bprh, bprl, csr);
907 #endif
908 
909 		if (csr & SI_CSR_BPCON) {
910 			/* have SI_CSR_BPCON */
911 			cp[-1] = (bprl & 0xff00) >> 8;
912 		} else {
913 			switch (csr & SI_CSR_LOB) {
914 			case SI_CSR_LOB_THREE:
915 				cp[-3] = (bprh & 0xff00) >> 8;
916 				cp[-2] = (bprh & 0x00ff);
917 				cp[-1] = (bprl & 0xff00) >> 8;
918 				break;
919 			case SI_CSR_LOB_TWO:
920 				cp[-2] = (bprh & 0xff00) >> 8;
921 				cp[-1] = (bprh & 0x00ff);
922 				break;
923 			case SI_CSR_LOB_ONE:
924 				cp[-1] = (bprh & 0xff00) >> 8;
925 				break;
926 			}
927 		}
928 	}
929 
930 out:
931 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRH, 0);
932 	SIREG_WRITE(ncr_sc, SIREG_DMA_ADDRL, 0);
933 
934 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTH, 0);
935 	SIREG_WRITE(ncr_sc, SIREG_DMA_CNTL, 0);
936 
937 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNTH, 0);
938 	SIREG_WRITE(ncr_sc, SIREG_FIFO_CNT, 0);
939 
940 	mode = NCR5380_READ(ncr_sc, sci_mode);
941 	/* Put SBIC back in PIO mode. */
942 	mode &= ~(SCI_MODE_DMA | SCI_MODE_DMA_IE);
943 	NCR5380_WRITE(ncr_sc, sci_mode, mode);
944 	NCR5380_WRITE(ncr_sc, sci_icmd, 0);
945 }
946